Learn CSS Variables by Building a City Skyline - Step 40

Tell us what’s happening:
Describe your issue in detail here.
I want to apply the linear-gradient to the background property of bb1a but it did not work when i run the syntax. someone can help me to fix it?
Your code so far

.bb1a{
width: 70%;
height: 10%;
background-color: var(–building-color1);
background:linear-gradient(–building-color1,–window-color1);
}


**Your browser information:**

User Agent is: <code>Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:105.0) Gecko/20100101 Firefox/105.0</code>

**Challenge:**  Learn CSS Variables by Building a City Skyline - Step 40

**Link to the challenge:**
https://www.freecodecamp.org/learn/2022/responsive-web-design/learn-css-variables-by-building-a-city-skyline/step-40

you are missing the var function.
Everytime you want the browser to understand a variable in CSS you have to pass it to a var function (just like you’re doing in the background-color line).
So you need 2 calls to var to complete this.

thank you, now it working.